A device system and method for growing oxide thin film using mist chemical vapor deposition

Abstract

The present invention provides a device system and method for growing oxide thin films by mist chemical vapor deposition, the device system comprising a feeding and atomizing unit, a mixing device, a reaction device and a vacuum generating device; the feeding and atomizing unit comprises at least two sets of feeding and atomizing components connected in parallel, each set of feeding and atomizing components comprises a feeding device and an atomizing device connected in series, and the atomizing device is connected to the mixing device; the bottoms of the feeding device and the atomizing device are independently provided with weighing sensors; a liquid start-stop device is provided between the feeding device and the atomizing device, a liquid level sensor is provided on the side wall of the atomizing device, and the liquid level sensor is electrically connected to the liquid start-stop device. The device system provided by the present invention improves the stability of atomization efficiency, enhances the real-time feedback function of the device, improves the uniformity of the gas flow field in the reaction area and the uniformity of substrate heating, thereby improving the film forming efficiency and quality.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and relates to a method for growing an oxide film, and in particular to a device system and method for growing an oxide film by using mist chemical vapor deposition. Background Art

[0002] Mist-CVD technology is a new type of oxide film-forming technology. This technology uses ultrasound to atomize the raw material solution, and then transports the atomized raw material to the reaction chamber through the transmission gas. After a series of reactions such as thermal decomposition, oxidation, reduction, and substitution in the reaction chamber, the film is formed on the substrate. It has the advantages of energy saving and safety, simple and easy equipment operation, and diversified raw material selection. In the semiconductor field, one of the applications of Mist-CVD technology is: epitaxial growth of Ga2O3 and other thin films on sapphire substrates.

[0003] At present, the following problems are common in general Mist-CVD devices: (1) Since the atomization efficiency of the atomizing gas is determined by the carrier gas flow rate and the characteristics of the ultrasonic transducer, maintaining the constant liquid level in the atomizing container plays a key role in stabilizing the atomization efficiency. However, in general Mist-CVD devices, the solution is usually replenished by manual replenishment or open-loop control of the pump, which will cause fluctuations in the liquid level and thus cause fluctuations in the atomization efficiency. (2) General Mist-CVD devices cannot view the atomization volume and atomization efficiency in real time, and cannot automatically warn of the remaining solution, so manual inspection is required, which is time-consuming and laborious. (3) General Mist-CVD devices generally form a pressure difference inside and outside the chamber through the delivery of carrier gas, thereby driving the atomizing gas, and then reducing the unstable flow field of the gas entering the reaction area through gas collision and rectification in the mixing chamber, while the uniformity of the gas flow field and the film formation stability still need to be further improved. (4) The general Mist-CVD device is only equipped with a gas rectifier chamber to stabilize the gas flow field during the reaction. Although it is suitable for a single atomization source, it is not well suited for multiple atomization sources. (5) The general Mist-CVD device sets the reaction chamber to bottom heating, and generally uses halogen tube heating for heating. In this case, a temperature difference will be formed between the lower and upper surfaces of the substrate. The arrangement of the halogen tubes causes uneven heating of the part close to the halogen tube and the part far from the halogen tube on the plane, thereby affecting the film quality.

[0004] In the article "Study on the Preparation of Gallium Oxide Thin Films by Mist-CVD and Their Characteristics", researchers designed a Mist-CVD deposition system based on the principle of chemical vapor deposition. The system uses a slit-type growth chamber, and the entire system consists of three parts: a fogging system, a fog mixing chamber, and a reaction chamber. However, the system only realizes the atomization of a single atomization source, and does not have the function of automatic solution replenishment. It is impossible to check the atomization efficiency and detect the remaining amount of solution. In addition, a pump is used in the exhaust system to exhaust gas, which has the problem of gas pulsation. The exhaust efficiency of the pump is controlled by voltage, and the adjustment effect is not stable.

[0005] It can be seen that how to provide a device system and method for growing oxide thin films using mist chemical vapor deposition, improve the stability of atomization efficiency, enhance the real-time feedback function of the device, improve the uniformity of the gas flow field in the reaction area and the uniformity of substrate heating, and thereby improve film formation efficiency and quality, has become an urgent problem that technical personnel in this field need to solve. Summary of the invention

[0006] The object of the present invention is to provide a device system and method for growing oxide thin films using mist chemical vapor deposition, the device system improves the stability of atomization efficiency, enhances the real-time feedback function of the device, improves the uniformity of the gas flow field in the reaction area and the uniformity of substrate heating, thereby improving the film formation efficiency and quality.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a device system for growing an oxide film by using mist chemical vapor deposition, the device system comprising a feed and atomization unit, a mixing device, a reaction device and a vacuum generating device connected in sequence.

[0009] The feeding and atomizing unit comprises at least two sets of feeding and atomizing components connected in parallel, each set of feeding and atomizing components comprises a feeding device and an atomizing device connected in series, and the atomizing device is connected to a mixing device.

[0010] The bottoms of the feeding device and the atomizing device are independently provided with weighing sensor devices.

[0011] A liquid start-stop device is provided between the feeding device and the atomizing device, a liquid level sensor is provided on the side wall of the atomizing device, and the liquid level sensor is electrically connected to the liquid start-stop device.

[0012] The device system provided by the present invention has at least two sets of feeding and atomizing components, and is combined with a mixing device to realize a mixed reaction or a sequential reaction of multiple different atomizing source gases; the weighing sensor device can weigh the solution in the feeding device and the atomizing device in real time, and then calculate the atomization efficiency of the reaction, thereby realizing real-time feedback on the remaining solution, without the need for manual inspection, saving time and effort; the liquid level sensor device combined with the material liquid start and stop device can control the start and stop of the material liquid in real time according to the liquid level height in the atomizing device, thereby realizing more accurate maintenance and control of the liquid level height and improving the stability of the atomization efficiency; the vacuum generating device improves the uniformity of the gas flow field in the reaction area by creating a negative pressure environment at the end of the reaction device, thereby improving the film forming efficiency and quality.

[0013] In the present invention, the atomization efficiency is calculated as follows: the sum of the weights of the feeding device and the atomization device is weighed by a weighing sensor device, which is recorded as G1; after ΔT time, the sum of the weights of the feeding device and the atomization device is weighed by a weighing sensor device, which is recorded as G2. The atomization efficiency during this period is V = (G1-G2) / ΔT.

[0014] Preferably, the feeding device comprises a material tank and a one-way valve arranged on the top of the material tank, and the air outside the material tank enters the interior of the material tank through the one-way valve, thereby balancing the air pressure inside and outside the material tank.

[0015] In the present invention, the material tank is made of a material that does not chemically react with the contained raw material liquid, for example, it can be quartz, metal or polymer material, which is not particularly limited here.

[0016] Preferably, the atomization device comprises an atomization tank and an ultrasonic atomizer.

[0017] In the present invention, the working principle of the ultrasonic atomizer is to generate a propagation pressure difference in the liquid by means of the high-frequency vibration of the piezoelectric element. The stronger the vibration, the greater the surface tension of the liquid. When the vibration intensity is sufficient, the liquid will eventually split to form atomized gas.

[0018] Specifically, the position of the piezoelectric element (or ultrasonic vibrator) in the ultrasonic atomizer is divided into two situations: (1) the ultrasonic vibrator is directly placed at the bottom of the atomization tank, that is, the ultrasonic vibrator is in direct contact with the solution, and the solution is atomized by high-frequency vibration; (2) the ultrasonic vibrator is connected to a medium container, and the medium container is filled with a medium (a liquid that allows ultrasonic waves to pass through, generally pure water), and a part of the atomization tank is immersed in the medium, that is, the ultrasonic vibrator is not in direct contact with the solution, thereby avoiding corrosion of the ultrasonic vibrator by the solution.

[0019] Preferably, the atomizing tank is provided with a carrier gas inlet, a dilution gas inlet and an atomizing gas outlet.

[0020] In the present invention, the carrier gas inlet can be arranged at the top of the atomizing tank or at the upper part of the side wall of the atomizing tank, as long as it is located above the surface of the solution in the atomizing tank, so it is not particularly limited here.

[0021] In the present invention, the carrier gas entering from the carrier gas inlet drives the atomizing gas to flow out from the atomizing gas outlet, and the greater the flow rate of the carrier gas, the higher the atomization efficiency. Therefore, the atomization efficiency can be changed by adjusting the carrier gas flow rate, thereby achieving flexible control of the atomization efficiency; the dilution gas enters from the dilution gas inlet, and increasing the flow rate of the dilution gas can increase the internal gas flow rate without increasing the atomization amount.

[0022] Preferably, a communicating vessel is provided on the side wall of the atomizing tank, and the liquid level sensor is fixed on the surface of the communicating vessel.

[0023] In the present invention, the raw material liquid enters the atomizing tank from the material tank for ultrasonic atomization, and the liquid level sensor device fixed on the surface of the communicating vessel detects the liquid level inside the atomizing tank in real time. When the liquid level sensor device cannot detect the liquid, an alarm is sounded, and feedback is given to the material liquid start-stop device for liquid replenishment. When liquid is detected again, feedback is given to the material liquid start-stop device to stop liquid replenishment, thereby achieving more accurate maintenance and control of the liquid level height and improving the stability of the atomization efficiency.

[0024] Preferably, the weighing sensor device comprises a weighing sensor and a tray, and the tray is used to support the material tank and the atomization tank.

[0025] Preferably, the liquid start-stop device comprises a start-stop switch and a delivery pump which are electrically connected to each other.

[0026] Preferably, the start-stop switch is electrically connected to the liquid level sensor device, and is used to receive a feedback signal from the liquid level sensor device and control the start and stop of the delivery pump.

[0027] Preferably, the delivery pump comprises any one of a peristaltic pump, a diaphragm pump or a syringe pump.

[0028] Preferably, the mixing device comprises a mixing chamber and an atomizing gas inlet and a mixed gas outlet arranged on the surface of the mixing chamber.

[0029] Preferably, an isolation valve is further provided between the atomizing gas outlet of the atomizing tank and the atomizing gas inlet of the mixing chamber.

[0030] In the present invention, the atomized gas generated by the atomizing tank flows into the mixing chamber through the atomizing gas inlet for full mixing, and the resulting mixed gas flows out through the mixed gas outlet. When only one atomized gas flows in, the isolation valves of the other channels are closed, thereby preventing the backflow of the atomized gas from polluting the other channels.

[0031] Preferably, the reaction device comprises a horizontal reaction chamber and upper and lower symmetrical heaters arranged outside the horizontal reaction chamber, namely: an upper heater and a lower heater.

[0032] In the present invention, the horizontal reaction chamber is made of a material that does not chemically react with the contained atomized gas, such as quartz, ceramic or metal material, which is not particularly limited here.

[0033] Preferably, according to the gas flow direction, the interior of the horizontal reaction chamber is divided into a rectifying chamber, a reaction chamber and a buffer chamber in sequence; the rectifying chamber has an airflow convergence structure, the reaction chamber is a narrow slit space, and the buffer chamber has an airflow divergence structure.

[0034] In the present invention, the rectifying chamber has an airflow convergence structure, which can rectify the atomized gas entering the horizontal reaction chamber, so that the airflow before it flows into the reaction chamber is more stable, thereby improving the uniformity of the gas flow field inside the subsequent reaction chamber; the reaction chamber is a narrow slit space, which can further promote the stability and uniformity of the gas flow field; the buffer chamber has an airflow divergence structure, which can prevent the gas flow rate at the tail end of the reaction chamber from being too fast, avoid the airflow directly hitting the inner wall of the tail end to form an unstable flow field, and increase the buffer space.

[0035] Preferably, the vertically symmetrical heater heats the upper and lower parts of the reaction chamber.

[0036] Preferably, the upper heater and the lower heater are independently infrared radiation heaters or induction heaters, and more preferably infrared radiation heaters.

[0037] In the present invention, the infrared radiation heater is made of ceramic or quartz material, and contains a heating resistor wire inside, and achieves the purpose of heating through the plane infrared heat radiation of the material. Compared with conventional halogen tubes, this heating method has a more uniform heat distribution for heating the substrate.

[0038] Preferably, the upper heater and the lower heater are independently connected to temperature feedback components.

[0039] In the present invention, the temperature feedback component includes a temperature measuring element and a temperature control switch, which can realize real-time measurement and control of the heating temperature of the upper heater and the lower heater.

[0040] Preferably, the vacuum generating device comprises a pneumatic vacuum generator or an electric vacuum generator, and more preferably a pneumatic vacuum generator.

[0041] In the present invention, the pneumatic vacuum generator is driven by pneumatics, and the gas flow from the air inlet to the exhaust port forms a negative pressure on the exhaust port, driving the exhaust port to exhaust outward, and the exhaust speed can be controlled by controlling the air pressure or flow rate; compared with the pump, the vacuum generator has a smaller volume, a more uniform flow rate, and no air flow pulsation.

[0042] In a second aspect, the present invention provides a method for growing an oxide thin film by mist chemical vapor deposition using the device system of the first aspect, the method comprising the following steps:

[0043] (1) preparing at least two raw material liquids and adding them into the feeding device respectively;

[0044] (2) The raw material liquid in the feeding device is passed into the atomizing device for atomization to obtain atomized gas, and at the same time, the liquid level height in the atomizing device is monitored in real time by a liquid level sensor device, and the liquid level in the atomizing device is maintained in a stable state in combination with the feed liquid start-stop device;

[0045] (3) passing the atomized gas into a mixing device for mixing to obtain a mixed gas;

[0046] (4) The mixed gas is introduced into a reaction device to perform mist chemical vapor deposition to grow an oxide film, and the remaining mixed gas is discharged through a vacuum generating device.

[0047] Preferably, the raw material solution in step (1) comprises any one of a gallium salt aqueous solution, an aluminum salt aqueous solution, an indium salt aqueous solution, an iron salt aqueous solution or a zinc salt aqueous solution, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of a gallium salt aqueous solution and an aluminum salt aqueous solution, a combination of a gallium salt aqueous solution and an indium salt aqueous solution, a combination of a gallium salt aqueous solution and an iron salt aqueous solution, or a combination of a gallium salt aqueous solution, an aluminum salt aqueous solution and an indium salt aqueous solution.

[0048] Preferably, the gallium salt in the gallium salt aqueous solution includes any one of gallium acetylacetate, gallium acetylacetonate, gallium vinylacetonate, gallium chloride or gallium bromide, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of gallium acetylacetate and gallium acetylacetonate, a combination of gallium acetylacetonate and gallium vinylacetonate, a combination of gallium vinylacetonate and gallium chloride, a combination of gallium chloride and gallium bromide, a combination of gallium acetylacetate, gallium acetylacetonate and gallium vinylacetonate, a combination of gallium acetylacetonate, gallium vinylacetonate and gallium chloride, or a combination of gallium vinylacetonate, gallium chloride and gallium bromide.

[0049] Preferably, the aluminum salt in the aluminum salt aqueous solution includes aluminum acetoacetate and / or aluminum acetylacetonate.

[0050] Preferably, the indium salt in the indium salt aqueous solution includes indium acetoacetate.

[0051] Preferably, the iron salt in the aqueous solution of iron salt comprises iron acetylacetonate.

[0052] Preferably, the zinc salt in the aqueous zinc salt solution comprises zinc chloride.

[0053] The atomization in step (2) includes ultrasonic atomization, and the ultrasonic frequency is 1-10 MHz, for example, 1 MHz, 1.5 MHz, 2 MHz, 2.5 MHz, 3 MHz, 3.5 MHz, 4 MHz, 4.5 MHz, 5 MHz, 5.5 MHz, 6 MHz, 6.5 MHz, 7 MHz, 7.5 MHz, 8 MHz, 8.5 MHz, 9 MHz, 9.5 MHz or 10 MHz, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0054] Preferably, the atomization in step (2) further comprises introducing a carrier gas into the atomization device.

[0055] Preferably, the mixing in step (3) further comprises introducing dilution gas into the mixing device.

[0056] Preferably, the carrier gas and the diluent gas independently include nitrogen and / or oxygen.

[0057] Preferably, the material of the oxide film in step (4) includes Ga2O3, (Al x Ga 1-x )2O3、(Al x In y Ga 1-x-y )2O3、(Fe x Ga 1-x )2O3 or ZnO.

[0058] Preferably, the growth temperature of the oxide film in step (4) is 300-800°C, for example, it can be 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C or 800°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] The device system provided by the present invention has at least two sets of feeding and atomizing components, and is combined with a mixing device to realize a mixed reaction or a sequential reaction of multiple different atomizing source gases; the weighing sensor device can weigh the solution in the feeding device and the atomizing device in real time, and then calculate the atomization efficiency of the reaction, thereby realizing real-time feedback on the remaining solution, without the need for manual inspection, saving time and effort; the liquid level sensor device combined with the material liquid start and stop device can control the start and stop of the material liquid in real time according to the liquid level height in the atomizing device, thereby realizing more accurate maintenance and control of the liquid level height and improving the stability of the atomization efficiency; the vacuum generating device improves the uniformity of the gas flow field in the reaction area by creating a negative pressure environment at the end of the reaction device, thereby improving the film forming efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 is a schematic diagram of the structure of the device system for growing an oxide thin film by mist chemical vapor deposition provided in Example 1;

[0062] Figure 2 This is a structural diagram of the atomization device in the device system provided in Example 4.

[0063] Among them: 10-feeding and atomizing components; 11-feeding device; 11a-material tank; 11b-one-way valve; 12-atomizing device; 12a-atomizing tank; 12b-ultrasonic atomizer; 12c-carrier gas inlet; 12d-dilution gas inlet; 12e-atomizing gas outlet; 12f-connecting vessel; 13-weighing sensor device; 13a-weighing sensor; 13b-tray; 14-material liquid start and stop device; 14a-delivery pump; 15-liquid level sensor; 20-mixing device; 20a-mixing chamber; 20b-atomizing gas inlet; 20c-mixing gas outlet; 21-isolating valve; 30-reaction device; 31-horizontal reaction chamber; 31a-rectifier chamber; 31b-reaction chamber; 31c-buffer chamber; 32-upper and lower symmetrical heater; 32a-upper heater; 32b-lower heater; 40-vacuum generating device. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0065] Example 1

[0066] This embodiment provides a device system for growing oxide thin films using mist chemical vapor deposition, such as Figure 1As shown, the device system includes a feeding and atomizing unit, a mixing device 20, a reaction device 30 and a vacuum generating device 40 connected in sequence; the feeding and atomizing unit includes two sets of feeding and atomizing components 10 connected in parallel, each set of feeding and atomizing components 10 includes a feeding device 11 and an atomizing device 12 connected in series, and the atomizing device 12 is connected to the mixing device 20; weighing sensor devices 13 are independently provided at the bottom of the feeding device 11 and the atomizing device 12; a material liquid start-stop device 14 is provided between the feeding device 11 and the atomizing device 12, a liquid level sensor 15 is provided on the side wall of the atomizing device 12, and the liquid level sensor 15 is electrically connected to the material liquid start-stop device 14.

[0067] In this embodiment, the feeding device 11 includes a material tank 11a and a one-way valve 11b arranged on the top of the material tank 11a. The air outside the material tank 11a enters the interior of the material tank 11a through the one-way valve 11b, thereby balancing the air pressure inside and outside the material tank 11a; the atomization device 12 includes an atomization tank 12a and an ultrasonic atomizer 12b arranged at the bottom of the atomization tank 12a. The top of the atomization tank 12a is provided with a carrier gas inlet 12c, a dilution gas inlet 12d and an atomization gas outlet 12e, the side wall of the atomization tank 12a is provided with a communicating vessel 12f, and the liquid level sensor 15 is fixed to the surface of the communicating vessel 12f. The weighing sensor device 13 includes a weighing sensor 13a and a tray 13b, and the tray 13b is used to support the material tank 11a and the atomization tank 12a; the material liquid start-stop device 14 includes a start-stop switch and a delivery pump 14a electrically connected to each other, and the start-stop switch is electrically connected to the liquid level sensor 15, and is used to receive the feedback signal of the liquid level sensor 15 and control the start and stop of the delivery pump 14a, and the delivery pump 14a is a peristaltic pump.

[0068] In this embodiment, the mixing device 20 includes a mixing chamber 20a and an atomizing gas inlet 20b and a mixing gas outlet 20c arranged on the surface of the mixing chamber 20a; an isolation valve 21 is also provided between the atomizing gas outlet 12e of the atomizing tank 12a and the atomizing gas inlet 20b of the mixing chamber 20a. The reaction device 30 includes a horizontal reaction chamber 31 and upper and lower symmetrical heaters 32 arranged outside the horizontal reaction chamber 31, which are respectively: an upper heater 32a and a lower heater 32b. According to the gas flow direction, the interior of the horizontal reaction chamber 31 is divided into a rectifying chamber 31a, a reaction chamber 31b and a buffer chamber 31c in sequence; the rectifying chamber 31a has an airflow convergence structure, the reaction chamber 31b is a narrow slit space, and the buffer chamber 31c has an airflow divergence structure. The upper and lower symmetrical heaters 32 heat the upper and lower parts of the reaction chamber 31b, and the upper heater 32a and the lower heater 32b are independently infrared radiation heaters, and the upper heater 32a and the lower heater 32b are independently connected to temperature feedback components (not shown in the figure), and the temperature feedback components include temperature measuring elements and temperature control switches, which can achieve real-time measurement and control of the heating temperatures of the upper heater 32a and the lower heater 32b. The vacuum generating device 40 is a pneumatic vacuum generator.

[0069] Example 2

[0070] This embodiment provides a device system for growing an oxide film using mist chemical vapor deposition. Except for removing the upper heater 32a and retaining only the lower heater 32b, the remaining structures and conditions are the same as those in Embodiment 1, so they are not described here in detail.

[0071] Example 3

[0072] This embodiment provides a device system for growing oxide thin films using mist chemical vapor deposition. Except that the feed and atomization units are changed to three sets of feed and atomization components 10 connected in parallel, the remaining structures and conditions are the same as those in Embodiment 1, so they are not described here.

[0073] Example 4

[0074] This embodiment provides a device system for growing an oxide film by mist chemical vapor deposition. The device system is based on the embodiment 1, but the atomizing device 12 is replaced by Figure 2 The structure shown is as follows: (1) the carrier gas inlet 12c is changed from the top of the atomizing tank 12a to the upper part of the side wall; (2) the tray 13b is replaced by a medium container, and the ultrasonic vibrator of the ultrasonic atomizer 12b is connected to the medium container, and the medium container is filled with pure water, and a part of the atomizing tank 12a is immersed in the pure water, that is, the ultrasonic vibrator is not in direct contact with the solution in the atomizing tank 12a, thereby avoiding corrosion of the ultrasonic vibrator by the solution.

[0075] In this embodiment, the rest of the structure and conditions of the device system are the same as those in Embodiment 1, and thus will not be described in detail here.

[0076] Comparative Example 1

[0077] This comparative example provides a device system for growing an oxide film by mist chemical vapor deposition, except that the feed and atomization unit is replaced by a set of feed and atomization components 10, and the mixing device 20 is removed, and the atomization device 12 is directly connected to the reaction device 30. The remaining structures and conditions are the same as those in Example 1, so they are not repeated here.

[0078] Comparative Example 2

[0079] This comparative example provides a device system for growing an oxide thin film using mist chemical vapor deposition. Except for removing the weighing sensor device 13, the remaining structures and conditions are the same as those of Example 1, so they are not described here in detail.

[0080] Comparative Example 3

[0081] This comparative example provides a device system for growing an oxide thin film using mist chemical vapor deposition. Except for removing the liquid level sensor 15, the remaining structures and conditions are the same as those of Example 1, so they are not described here in detail.

[0082] Comparative Example 4

[0083] This comparative example provides a device system for growing an oxide thin film by mist chemical vapor deposition. Except for removing the vacuum generating device 40, the rest of the structure and conditions are the same as those of Example 1, so they are not described in detail here.

[0084] Application Example 1

[0085] This application example uses the device system provided in Example 1 to perform mist chemical vapor deposition growth (Al x Ga 1-x )2O3 film, the specific method comprises the following steps:

[0086] (1) preparing two raw material solutions, namely: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid) and an aluminum salt aqueous solution (aluminum acetylacetonate + pure water + hydrochloric acid); adding the above two raw material solutions to the feeding device 11 respectively, and placing a sapphire substrate in the center of the reaction chamber 31b;

[0087] (2) The raw material liquid in the feeding device 11 and the carrier gas (oxygen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0088] (3) introducing the atomized gas and the diluent gas (oxygen) into the mixing device 20 for mixing to obtain a mixed gas;

[0089] (4) The mixed gas is introduced into the reaction device 30 and fog chemical vapor deposition growth (Al) is performed at 500°C. x Ga 1-x )2O3 film, and the remaining mixed gas is discharged through the vacuum generating device.

[0090] In this application example, the obtained (Al x Ga 1-x ) The x value in the 2O3 film is appropriately adjusted according to the atomization efficiency V of each feed and atomization component 10, specifically: when the atomization efficiency V of the feed and atomization component 10 of the gallium salt aqueous solution is increased Ga and / or reduce the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al When the atomization efficiency V of the feed and atomization assembly 10 of the gallium salt aqueous solution is reduced, the x value gradually decreases; Ga And / or increase the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al , the x value gradually increases.

[0091] The atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G1; after a period of ΔT, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G2. The atomization efficiency V during this period of time is V = (G1-G2) / ΔT.

[0092] Application Example 2

[0093] This application example uses the device system provided in Example 2 to perform mist chemical vapor deposition growth (Fe x Ga 1-x )2O3 film, the specific method comprises the following steps:

[0094] (1) preparing two raw material solutions, namely: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid) and an iron salt aqueous solution (iron acetylacetonate + pure water + hydrochloric acid); adding the above two raw material solutions to the feeding device 11 respectively, and placing a sapphire substrate in the center of the reaction chamber 31b;

[0095] (2) The raw material liquid in the feeding device 11 and the carrier gas (nitrogen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0096] (3) introducing the atomized gas and the diluent gas (nitrogen) into the mixing device 20 for mixing to obtain a mixed gas;

[0097] (4) The mixed gas is introduced into the reaction device 30, and the mist chemical vapor deposition growth (Fe x Ga 1-x )2O3 film, and the remaining mixed gas is discharged through the vacuum generating device.

[0098] In this application example, the obtained (Fe x Ga 1-x ) The x value in the 2O3 film is appropriately adjusted according to the atomization efficiency V of each feed and atomization component 10, specifically: when the atomization efficiency V of the feed and atomization component 10 of the gallium salt aqueous solution is increased Ga and / or reduce the atomization efficiency V of the feed and atomization assembly 10 of the iron salt aqueous solution Fe When the atomization efficiency V of the feed and atomization assembly 10 of the gallium salt aqueous solution is reduced, the x value gradually decreases; Ga and / or increase the atomization efficiency V of the feed and atomization assembly 10 of the iron salt aqueous solution Fe , the x value gradually increases.

[0099] The atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G1; after a period of ΔT, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G2. The atomization efficiency V during this period of time is V = (G1-G2) / ΔT.

[0100] Compared with Application Example 1, since the reaction device 30 in the device system used in this application example only has a lower heater 32b and no upper heater 32a, the substrate is heated unevenly during the thin film growth process, and there is a temperature difference between the upper and lower surfaces, which affects the film quality to a certain extent.

[0101] Application Example 3

[0102] This application example uses the device system provided in Example 3 to perform mist chemical vapor deposition growth (Al x In y Ga 1-x-y )2O3 film, the specific method comprises the following steps:

[0103] (1) preparing three kinds of raw material solutions, namely: gallium salt aqueous solution (gallium acetoacetate + pure water), aluminum salt aqueous solution (aluminum acetoacetate + pure water) and indium salt aqueous solution (indium acetoacetate + pure water); adding the above three kinds of raw material solutions into the feeding device 11 respectively, and placing the sapphire substrate in the center of the reaction chamber 31b;

[0104] (2) The raw material liquid in the feeding device 11 and the carrier gas (nitrogen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0105] (3) introducing the atomized gas and the diluent gas (nitrogen) into the mixing device 20 for mixing to obtain a mixed gas;

[0106] (4) The mixed gas is introduced into the reaction device 30 and fog chemical vapor deposition growth (Al) is performed at 500°C. x In y Ga 1-x-y )2O3 film, and the remaining mixed gas is discharged through the vacuum generating device.

[0107] In this application example, the obtained (Al x In y Ga 1-x-y The x value and y value in the )2O3 film are appropriately adjusted according to the atomization efficiency V of each feed and atomization component 10. The specific adjustment principle is similar to that of Application Example 1 and Application Example 2, so it will not be repeated here.

[0108] The atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G1; after a period of ΔT, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G2. The atomization efficiency V during this period of time is V = (G1-G2) / ΔT.

[0109] Comparative application example 1

[0110] This comparative application example uses the device system provided in comparative example 1 to perform mist chemical vapor deposition to grow Ga2O3 thin film. The specific method includes the following steps:

[0111] (1) Prepare a raw material solution: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid); add the above raw material solution into the feeding device 11, and at the same time place a sapphire substrate into the center of the reaction chamber 31b;

[0112] (2) The raw material liquid in the feeding device 11 and the carrier gas (oxygen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0113] (3) The atomized gas and the diluent gas (oxygen) are introduced into the reaction device 30, and the Ga2O3 thin film is grown by mist chemical vapor deposition at 500°C. The remaining mixed gas is discharged through a vacuum generating device.

[0114] In this comparative application example, the atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor device 13, which is recorded as G1; after ΔT time, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor device 13 again, which is recorded as G2. The atomization efficiency V during this period of time = (G1-G2) / ΔT.

[0115] Compared with Application Example 1, this comparative application example is only applicable to a single atomization source, and is not applicable to a mixed reaction or sequential reaction of multiple different atomization source gases.

[0116] Comparative Application Example 2

[0117] This comparative application example uses the device system provided in comparative example 2 to perform mist chemical vapor deposition growth (Al x Ga 1-x )2O3 film, the specific method comprises the following steps:

[0118] (1) preparing two raw material solutions, namely: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid) and an aluminum salt aqueous solution (aluminum acetylacetonate + pure water + hydrochloric acid); adding the above two raw material solutions to the feeding device 11 respectively, and placing a sapphire substrate in the center of the reaction chamber 31b;

[0119] (2) The raw material liquid in the feeding device 11 and the carrier gas (oxygen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state;

[0120] (3) introducing the atomized gas and the diluent gas (oxygen) into the mixing device 20 for mixing to obtain a mixed gas;

[0121] (4) The mixed gas is introduced into the reaction device 30 and fog chemical vapor deposition growth (Al) is performed at 500°C. x Ga 1-x )2O3 film, and the remaining mixed gas is discharged through the vacuum generating device.

[0122] Compared with Application Example 1, this comparative application example cannot weigh the weight of the solution in the feeding device 11 and the atomizing device 12 in real time, and thus cannot calculate the atomization efficiency V of the reaction, making it difficult to obtain (Al x Ga 1-x )2O3 film to precisely adjust the x value.

[0123] Comparative Application Example 3

[0124] This comparative application example uses the device system provided in comparative example 3 to perform mist chemical vapor deposition growth (Al x Ga 1-x )2O3 film, the specific method comprises the following steps:

[0125] (1) preparing two raw material solutions, namely: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid) and an aluminum salt aqueous solution (aluminum acetylacetonate + pure water + hydrochloric acid); adding the above two raw material solutions to the feeding device 11 respectively, and placing a sapphire substrate in the center of the reaction chamber 31b;

[0126] (2) The raw material liquid in the feeding device 11 and the carrier gas (oxygen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level in the atomizing device 12 is manually checked at regular intervals, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0127] (3) introducing the atomized gas and the diluent gas (oxygen) into the mixing device 20 for mixing to obtain a mixed gas;

[0128] (4) The mixed gas is introduced into the reaction device 30 and fog chemical vapor deposition growth (Al) is performed at 500°C. x Ga 1-x )2O3 film, and the remaining mixed gas is discharged through the vacuum generating device.

[0129] In this comparative application example, the obtained (Al x Ga 1-x ) The x value in the 2O3 film is appropriately adjusted according to the atomization efficiency V of each feed and atomization component 10, specifically: when the atomization efficiency V of the feed and atomization component 10 of the gallium salt aqueous solution is increased Ga and / or reduce the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al When the atomization efficiency V of the feed and atomization assembly 10 of the gallium salt aqueous solution is reduced, the x value gradually decreases; Ga And / or increase the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al , the x value gradually increases.

[0130] The atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G1; after a period of ΔT, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G2. The atomization efficiency V during this period of time is V = (G1-G2) / ΔT.

[0131] Compared with Application Example 1, this comparative application example requires manual inspection of the liquid level in the atomizing device 12 at regular intervals, which is time-consuming and labor-intensive, and it is difficult to achieve accurate maintenance and control of the liquid level.

[0132] Comparative Application Example 4

[0133] This comparative application example uses the device system provided in comparative example 4 to perform mist chemical vapor deposition growth (Al x Ga 1-x )2O3 film, the specific method comprises the following steps:

[0134] (1) preparing two raw material solutions, namely: a gallium salt aqueous solution (gallium acetylacetonate + pure water + hydrochloric acid) and an aluminum salt aqueous solution (aluminum acetylacetonate + pure water + hydrochloric acid); adding the above two raw material solutions to the feeding device 11 respectively, and placing a sapphire substrate in the center of the reaction chamber 31b;

[0135] (2) The raw material liquid in the feeding device 11 and the carrier gas (oxygen) are introduced into the atomizing device 12 for ultrasonic atomization, and the ultrasonic frequency is 5 MHz to obtain atomized gas. At the same time, the liquid level height in the atomizing device 12 is monitored in real time by the liquid level sensor 15, and the liquid start-stop device 14 is combined to maintain the liquid level in the atomizing device 12 in a stable state; during the atomization process, the weight G of the feeding device 11 and the atomizing device 12 is weighed in real time by the weighing sensor 13, and the atomization efficiency V of each feeding and atomizing component 10 is calculated;

[0136] (3) introducing the atomized gas and the diluent gas (oxygen) into the mixing device 20 for mixing to obtain a mixed gas;

[0137] (4) The mixed gas is introduced into the reaction device 30 and fog chemical vapor deposition growth (Al) is performed at 500°C. x Ga 1-x )2O3 thin film.

[0138] In this comparative application example, the obtained (Al x Ga 1-x ) The x value in the 2O3 film is appropriately adjusted according to the atomization efficiency V of each feed and atomization component 10, specifically: when the atomization efficiency V of the feed and atomization component 10 of the gallium salt aqueous solution is increased Ga and / or reduce the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al When the atomization efficiency V of the feed and atomization assembly 10 of the gallium salt aqueous solution is reduced, the x value gradually decreases; Ga And / or increase the atomization efficiency V of the feed and atomization assembly 10 of the aluminum salt aqueous solution Al , the x value gradually increases.

[0139] The atomization efficiency V is calculated as follows: the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G1; after a period of ΔT, the sum of the weights of the feeding device 11 and the atomization device 12 is weighed by the weighing sensor 13, which is recorded as G2. The atomization efficiency V during this period of time is V = (G1-G2) / ΔT.

[0140] Compared with Application Example 1, this comparative application example forms a pressure difference inside and outside the horizontal reaction chamber 31 by delivering the carrier gas, thereby driving the atomizing gas. The uniformity of the gas flow field and the film formation stability are not as good as those in Application Example 1.

[0141] It can be seen that the device system provided by the present invention has at least two sets of feeding and atomization components, and is combined with a mixing device to realize a mixed reaction or a sequential reaction of multiple different atomization source gases; the weighing sensor device can weigh the solution in the feeding device and the atomization device in real time, and then calculate the atomization efficiency of the reaction, thereby realizing real-time feedback on the remaining solution, without the need for manual inspection, saving time and effort; the liquid level sensor device combined with the liquid start and stop device can control the start and stop of the liquid in real time according to the liquid level height in the atomization device, thereby realizing more accurate maintenance and control of the liquid level height and improving the stability of the atomization efficiency; the vacuum generating device improves the uniformity of the gas flow field in the reaction area by creating a negative pressure environment at the end of the reaction device, thereby improving the film forming efficiency and quality.

[0142] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A device system for growing oxide thin films using mist chemical vapor deposition, characterized in that: The device system comprises a feeding and atomizing unit, a mixing device, a reaction device and a vacuum generating device connected in sequence; The feeding and atomizing unit comprises at least two sets of feeding and atomizing components connected in parallel, each set of feeding and atomizing components comprises a feeding device and an atomizing device connected in series, and the atomizing device is connected to a mixing device; The feeding device includes a material tank and a one-way valve arranged on the top of the material tank, and the air outside the material tank enters the inside of the material tank through the one-way valve; The bottoms of the feeding device and the atomizing device are independently provided with weighing sensor devices; A liquid start-stop device is provided between the feeding device and the atomizing device, a liquid level sensor is provided on the side wall of the atomizing device, and the liquid level sensor is electrically connected to the liquid start-stop device; The reaction device comprises a horizontal reaction chamber and upper and lower symmetrical heaters arranged outside the horizontal reaction chamber, which are respectively: an upper heater and a lower heater; The vacuum generating device comprises a pneumatic vacuum generator or an electric vacuum generator.

2. The device system according to claim 1, characterized in that: The atomization device comprises an atomization tank and an ultrasonic atomizer.

3. The device system according to claim 2, characterized in that: The atomizing tank is provided with a carrier gas inlet, a dilution gas inlet and an atomizing gas outlet.

4. The device system according to claim 2, characterized in that: The side wall of the atomizing tank is provided with a communicating vessel, and the liquid level sensor device is fixed on the surface of the communicating vessel.

5. The device system according to claim 1, characterized in that: The weighing sensor device comprises a weighing sensor and a tray, and the tray is used for supporting a material tank and an atomizing tank.

6. The device system according to claim 1, characterized in that: The liquid start-stop device comprises a start-stop switch and a delivery pump which are electrically connected to each other.

7. The device system according to claim 6, characterized in that: The start-stop switch is electrically connected to the liquid level sensor device.

8. The device system according to claim 6, characterized in that: The delivery pump includes any one of a peristaltic pump, a diaphragm pump or a syringe pump.

9. The device system according to claim 1, characterized in that: The mixing device comprises a mixing chamber and an atomizing gas inlet and a mixed gas outlet arranged on the surface of the mixing chamber.

10. The device system according to claim 2, characterized in that: An isolation valve is also provided between the atomizing gas outlet of the atomizing tank and the atomizing gas inlet of the mixing chamber.

11. The device system according to claim 1, characterized in that: According to the gas flow direction, the interior of the horizontal reaction chamber is divided into a rectifying chamber, a reaction chamber and a buffer chamber in sequence; the rectifying chamber has an airflow convergence structure, the reaction chamber is a narrow slit space, and the buffer chamber has an airflow divergence structure.

12. The device system according to claim 1, characterized in that: The vertically symmetrical heater heats the upper and lower parts of the reaction chamber.

13. The device system according to claim 1, characterized in that: The upper heater and the lower heater are independently infrared radiation heaters or induction heaters.

14. The device system according to claim 13, characterized in that: The upper heater and the lower heater are independently infrared radiation heaters.

15. The device system according to claim 1, characterized in that: The upper heater and the lower heater are respectively and independently connected with temperature feedback components.

16. The device system according to claim 1, characterized in that: The vacuum generating device is a pneumatic vacuum generator.

17. A method for growing an oxide thin film by mist chemical vapor deposition using the device system as claimed in any one of claims 1 to 16, characterized in that: The method comprises the following steps: (1) preparing at least two raw material liquids and adding them into the feeding device respectively; (2) The raw material liquid in the feeding device is passed into the atomizing device for atomization to obtain atomized gas, and at the same time, the liquid level height in the atomizing device is monitored in real time by a liquid level sensor device, and the liquid level in the atomizing device is maintained in a stable state in combination with the feed liquid start-stop device; (3) passing the atomized gas into a mixing device for mixing to obtain a mixed gas; (4) The mixed gas is introduced into a reaction device to perform mist chemical vapor deposition to grow an oxide film, and the remaining mixed gas is discharged through a vacuum generating device.

18. The method according to claim 17, characterized in that The raw material solution in step (1) includes any one of a gallium salt aqueous solution, an aluminum salt aqueous solution, an indium salt aqueous solution, an iron salt aqueous solution or a zinc salt aqueous solution, or a combination of at least two thereof.

19. The method according to claim 18, characterized in that The gallium salt in the gallium salt aqueous solution includes any one of gallium acetoacetate, gallium acetylacetonate, gallium vinylacetonate, gallium chloride or gallium bromide, or a combination of at least two thereof.

20. The method according to claim 18, characterized in that The aluminum salt in the aluminum salt aqueous solution includes aluminum acetoacetate and / or aluminum acetylacetonate.

21. The method according to claim 18, characterized in that The indium salt in the indium salt aqueous solution includes indium acetoacetate.

22. The method according to claim 18, characterized in that The iron salt in the iron salt aqueous solution includes iron acetylacetonate.

23. The method according to claim 18, characterized in that The zinc salt in the zinc salt aqueous solution includes zinc chloride.

24. The method according to claim 17, characterized in that The atomization in step (2) includes ultrasonic atomization, and the ultrasonic frequency is 1-10 MHz.

25. The method according to claim 17, characterized in that The atomization in step (2) also includes introducing a carrier gas into the atomization device.

26. The method according to claim 25, characterized in that The mixing in step (3) also includes introducing dilution gas into the mixing device.

27. The method according to claim 26, characterized in that The carrier gas and the diluent gas independently include nitrogen and / or oxygen.

28. The method according to claim 17, characterized in that The material of the oxide film in step (4) includes Ga2O3, (Al x Ga 1-x )2O3、(Al x In y Ga 1-x-y )2O3、(Fe x Ga 1-x )2O3 or ZnO.

29. The method according to claim 17, characterized in that The growth temperature of the oxide film in step (4) is 300-800°C.

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